Document DE 196 00 852 A1 teaches of an anti-rotationally secured tappet of a valve drive of an internal combustion engine, preferably a bucket tappet composed of a base and a skirt, that is arranged between a cam and a valve and is guided in a receiving bore of a cylinder head. An anti-rotation component is arranged in a recess of the skirt, which anti-rotation component is guided in a guide groove of the cylinder head. The anti-rotation component is designed as an elastic spring element and consists of a back as well as two clips attached thereto, which clips are clipped into two longitudinal slits in the skirt of the tappet. It is disadvantageous that constructed space is greatly limited owing to the length of the clips on the interior of the tappet and, moreover, the two legs of both clips must have a high degree of spring preload in order to ensure a necessarily tight fit of the anti-rotation component so that with thin-walled skirts, in particular, an unacceptably high demand of the material of the skirt cannot be excluded.
Document DE 195 01 061 A1, for example, teaches of a further anti-rotationally secured tappet.